Rotary engine.



F. P. HUMMEL.

ROTARY ENGINE.

APPLICATION FILED snPT.1a,191o.

Patented May 14, 1912.

2 BHEBTBfBHBET 1.

COLUMBIA vLANnaR/Pn co., WASHINGTON. D. c.

F. P. HUMMEL.

ROTARY ENGINE.

v APPLIATON FILED SEPT. 19,1910. 1,026,165, Patented May 14, 1912.

2 SHEETS-SHEET 2.

fnl/Enlaz- /fafney IED SATES PATENT OFFICE.

FRANKLIN P. HUMMEL, OF BELLEVE, OHIO, ASSIGNOR OF ONE-THIRD TO FRANK A. HIGGINS, OF BELLEVUE, OHIO,

ROTARY ENGINE.

Specification of Letters Patent.

Patented May 14, 1912.

To all whom it may concern Be it known that I, FRANKLIN I). HUM- MEL, a citizen of the United States, residing at- Bellevue, in the county of Ifliuron and State of Ohio, have invented a certain new and useful Improvement in Rotary Engines, of which the following is a full, clear, and exact description, reference being had to the accompanying drawings.

This invention relates to rotary engines and its object is to provide an engine of this type with means for positively moving the piston blades in and out o-f the rotor and at the same time preventing the leakage of steam from the high pressure to the low pressure side of the engine or through the shaft bearings; to provide simple and ellicient means for lubricating the working parts; to increase the efficiency of machines of this class; and to decrease the cost of manufacture thereof.

Other objects and advantages will appear from the following description and claims.

Specifically, this invention is an improvement upon that forming the subject of my copending application filed May 7th, 1910, Serial Number' 559,995. In that application I have described and claimed a rotary engine having a cylinder of elliptical cross section and having at each end an elliptical cam groove surrounding said cylinder. A rotor is mounted in said cylinder and carries radially movable piston blades adapted to follow the curvature of the cylinder wall and having rollers running in said cam groove to positively hold the blades in contact with the cylinder wall at all points. I have found, however, that the expense of cutting such a groove is rather high and the ditlieulty of preventing leakage of steam past the rollers is very great. I have now devised a system including a circular groove which permits cheap manufacture and avoidance of leakage.

One embodiment of my invention is shown in the accompanying drawing in which- Figure 1 is an end view of the cylinder illustrated in Fig. 2 the end plate and cover plate being removed so as to show an end view of the rotor together with the blade hangers and cam ring substantially on the line 1-1 of Fig. 3; Fig. 2 is a central, lo-ngitudinal, cross-sectional view on the line 2-2 of Fig. 1; Fig. 3 is a transverse cent-ral section of cylinder and rotor at right angles to the section illustrated in Fig. 2; Fig. 4 1s an inside face View of the cam ring; Fig. is a sectional view of the same taken on the line 5--5 of Fig. 4; Fig. 6 is a face view of one of the closure plates; Fig. 7 is an end View of the naked cylinder and casing; Fig. 8 is the view of a section of the closure plate taken on the line 8-8 of Fig. (3; Fig. 9 is an enlarged detail sectional view of the cam ring and adjacent parts; and Fig. 10 is a View of one of the rollers disassembled.

Describing the parts by reference characters, my engine comprises a horizontal casing l supported on a base 2 and having at its top a steam chest 3. This casing is formed with a cylinder bore 4 elliptical in cross section, as shown in Figs. 1, 3 and 7, and having at its lowest point an outlet port 5 connected by means of the outlet chamber 6 with the main exhaust pipe 7. Disposed on opposite sides of the cylinder are the similar cut-olf valves 8 and 9 connected with the cylinder bore by the ports 10 and 11, respectively, and connected with the reversing valve 12 in the bottom of the steam chest by ducts 13 and 14, respectively. lVithin the cylinder bore and closely fitting the upper semicylindrical interior thereof is the rotor 15 keyed to the shaft 16 and having radial, radially movable blades 17. Each of these blades consists of a sliding member 18 fitting snugly in a radial recess in the rotor body and having a longitudinal groove at the bottom receiving the base member' 19 and springs 19. The other edge of Athe member 18 is formed with a rounded groove carrying the shoe 20 which is adapted to bear evenly against the cylinder wall in all positions of the rotor. Hangers 21 are connected at their inner ends to the base members 19 and at their outer ends to the cam ring hereinafter described. The reversing valve 12 is formed with an opening 22 on one side adapted to throw one of the ducts 13 or 14 into communication with the steam chest and with a longitudinal passage 23-on the other side connected with an axial bore 24 at a farther' point in the reversing valve and adapted to register with the other of the ducts 14 or 13. So far the construction is exactly the same as that described in the former application and further description of the arrangement and operation of these parts is deemed unnecessary. In that application the cam groove was made of elliptical shape parallel with the cylinder wall. In the present case I form this groove as a true circle as illustrated at 25 in Figs. 1 and 7 and in dotted lines in Fig. 3. In this groove I place a ring 26, which ring has an internal Harige 27 reaching substantially to the edge of the cylinder bore at its widest point. The part of the ring which fits into the groove is provided with spaced rollers 28 set in suitable recesses, saidv rollers preferably consisting of inner and outerconcentric shells 28a and 28b (Fig. 10) pivoted on studs 29. These rollers may bear either against the inside or the outside of the cam groove.

Each of the hangers 21 is attached to the cam ring 26 but the attachment must not be rigid since the cam ring and rotor revolve upon different axes and the distance between adjacent hangers must be allowed to vary according to their position in the cylinder. In order to effect this, without at the same time permitting the leakage of steam from one side of the blade to the other, I proceed as follows. The internal flange 27 of the cam ring is made of considerable thickness as shown in Fig. 9 and in Vits outer face arcuate grooves 30 are cut. These grooves are. made rather close to the inside edge of the ring flange and their inner wall is cut away as at 31 enough to allow the hanger 21 to project thcreover. An arcuate block 32 is snugly but slidably fitted within each of the grooves 30,the block being sufficiently shorter than the groove to allow the shifting necessary to the operation of the rotor. The outer edge of each of the blocks carries a semicircular recess 33 at its middle point, and one hanger 21 is pivoted upon a stud 34 at the center of this recess so as to have a limited angular movement with respect thereto as shown in Fig. 1. The cam ring, sliding block and hanger are smoothly faced off at their front sides as shown in Fig. 9.

Between the cylinder bore and the cam groove a narrower groove 35 is formed, said narrow groove containing a packing ring 36 urged outwardly by spaced spiral springs 37. Preferably this groove and ring are wider at one side than at the other and the ring is split at its narrowest part, as shown in Fig. 7 since this causes the ring to expand with substantially the same force in all directions and also prevents rotation of the ring. It will thus be seen that when the cam ring 26 is positioned in the cam groove 25 the flange 27 of the ring will bear against this packing ring 36 and leakage behind the ring will eifectually be prevented. Moreover, the construction of blocks 32 and hangers 21 prevents the leakage of steam from one side of the blade to the other.

The hangers are, set in grooves in the end face of the rotor, so that their faces are practically flush with the end of the rotor body. A flat circular cover plate 38 is rigidly attached to the rotor by means of bolts passing through holes and engaging the body of the rotor. This cover plate has a central perforation 40 through which the shaft 16 closely passes, and a groove 41 near the external edge of its inner face adapted to receive a packing ring 42 and spaced springs 43. This packing ring is preferably of the same shape as ring 35 and for the same reason, viz: to produce an equal expansion thereof and to prevent its rotation. When in assembled position this plate closely covers the end of the cylinder, and so snugly incloses the hangers 21 as to prevent the leakage of steam therearound. The packing ring 42 engages the cam ring 26 upon its flat surface between its outer periphery and the outer line of the grooves 30. lVhen the rotor revolves the cover plate rotates with it while the cam ring also rotates but in a different axis. A continuous shifting, therefore, takes place between the cover plate and the cam ring but never of such magnitude as to move the packing ring 42 outside of the limits indicated. By the action of the two packing rings 36 and 42 the steam is positively retained in the cylinder, and by the close fitting arrangement of hangers 21, cam ring 26, and blocks 32 steam is prevented from leaking from one side of the blades to the other side.

The casing is exte-nded beyond the cam groove as at 44 and squared ofip to receive the end plates 45 through which the shaft 16 extends, stuffing boxes 46 being formed on these end plates. The chamber 47 thus formed is packed with vaseline or other lubricant and in this way the cam ring and bearings are plentifully lubricated.

In order to lubricate the blades and the interior of the cylinder the shaft 16 is provided with a longitudinal duct 48 ending in radial ducts 49 delivering into the blade slots in the rotor. Oil can thus be introduced into the rotor where it is distributed by the pumping action of the blades and by centrifugal action.

The operation of the device is as follows: As the rotor revolves the cam ring 26 is carried' along by the contact of the ascending block 32 with the end of its groove. The hangers 21 compel the base members 19 of the blades to move in a substantially circular path about the center of revolution o-f the cam ring which is coincident with the center of the cylinder, and thus the blades are positively drawn in and out of their slots. The blades are enabled to follow the substantially flat sides of the cylinder by compressing the springs 19a, the shoes 20 being provided with pins 202L at their ends workan advantage inasmuch as it causes the blades to hug the cylinder wall at these points with an increased pressure, since previous experience has demonstrated a tendency to leak at this point. During this rotation the cover plate is also revolving at the same rate as the rotor and cam ring but shifting back and forth thereover, as above described.

rfhe operation of the steam upon the r'otor has been so fully described in the copending application that little need be said on that point. With the reversing valve 1Q adjusted to the position shown in Fig. 3 steam will pass from the steam chest 3 through duct 14, cut-off valve 9 which is monientarily opened by means connected with the shaft but not shown herein), and port .1,1 into the interior of the cylinder' where it presses upon t-he exposed piston blade both directly and expansively until the blade has passed the exhaust port 5. The larger part of the steam escapes through this port and pipe 7, but

such back pressure as may exist prevents complete clearance of the steam and some will be trapped by the advancing side of the piston blade beyond the exhaust port. This par't of the charge finds free exit from the cylinder by way of port l0, cut-ott valve 8 (which is set in open position), duct 13, passage 23, and bore 24. In order yet more completely to eliminate back pressure, I contemplate attaching a condenser to bore 24 of the reversing valve as indicated in Fig. 2. In this manner a partial vacuum may be obtained in what would otherwise be a dead sector of the cylinder, and by the use of a very much smaller condenser than would be required to accommodate the entire exhaust from the engine.

Having thus described my invention, what I claim is 1. A rotary engine comprising in combination a cylinder, a rotor in said cylinder and eccentric thereto, radially movable blades car'ried by said rotor, a circular cam groove surrounding said cylinder, a ring in said cam groove, and operative connections between said blades and said ring for causing the blades to follow the curvature of the cylinder wall.

2. A rotary engine comprising in combination a cylinder, a rotor in said cylinder and eccentric thereto, radially movable blades carried by said rotor, a circular cam groove surrounding said cylinder and concentric therewith, a ring in said cam groove, and operative connections between said blades and said ring for causing the blades to follow the curvature of the cylinder wall.

3. A rotary engine comprising in combination a cylinder, a rotor in said cylinder and eccentric thereto, radially movable blades carried by said rotor', a circular cam groove surrounding said cylinder, a groove between the cylinder bore and said cam groove, packing in said intermediate groove, a ring in said cam groove, said ring having an internal flange overlying said packing and approaching the cylinder' bore, and operative connections between said blades and said ring for causing the blades to :follow the curvature of the cylinder wall.

ll. A rotary engine comprising in combination a cylinder, a rotor in said cylinder and eccentric thereto, radially movable blades carried by said rotor, a circular cam groove surrounding said cylinder and concentric therewith, a groove between the cylinder bore and said cam groove, packing in said intermediate groove, a ring in said cam groove, said r'ing having an internal flange overlying said packing and approaching the cylinder bore, and operative connections between said blades and said ring for causing the blades to follow the curvature of the cylinder wall.

A rotary engine ctmiprising in combination a cylinder,ra rotor in said cylinder and eccentric thereto, radially movable blades carried by said rotor, hangers connected with said blades and lying substantially flush with the end of the rotor body, a cam groove surrounding the en d of the cylinder, means connected with said hangers and engaging said cam groove for causing the blades to follow the curvature of the cylinder wall, a cover plate attached to the, end of the rotor, and packing means carried by said cover plate and engaging the firstmentioned means tor sealing the end of the cylinder'.

G. A rotary engine comprising in combination a cylinder, a rotor in said cylinder and eccentric thereto, .radially movable blades carried by said rotor, hangers connecting with said blades and lying substantially flush with the end ot the rotor body, a circular cam groove surrounding the end of the cylinder, a ring in said cam groove and having a flat outer `tace', operative connections between said hangers and said ring whereby said blades may be caused to tollow the curvature oi. the cylinder Vall during the rotation of the rotor, a cover plate attached to the end of the rotor, and packing means carried by said cover plate and engaging the flat surface of said ring for sealing the end of the cylinder.

7. A rotary engine comprising in combination a cylinder, a rotor in said cylinder and eccentric thereto. radially movable' blades carried by said rotor, hangers connected with said blades and lying substantially flush with the end of the rotor body, a circular cam groove surrounding the end of the cylinder', a groove between the cylinder bore and said cam groove, packing in said intermediate groove, a ring in said cam groove, said ring having an internal flange overlying said packing and also having a flat outer face, operative connections between said hangers and said ring whereby said blades may be caused to follow the curvature of the cylinder wall during the rotation of the rotor, a cover plate attached to thefend of the rotor, and packing means carried by said cover plate and engaging the flat surface of said ring for sealing the end of the cylinder.

8. A rotary engine comprising in combination a cylinder, a rotor in said cylinder and eccentric thereto, radially movable blades carried by said rotor, hangers carried by said blades and extending outside the circumference of the rotor, a circular cam groove surrounding said cylinder, a ring in said groove, spaced arcuate grooves in said ring opposite each blade, blocks shorter than said grooves and slidable therein, and connections between said hangers and said blocks.

9. A rotary engine comprising in combination a cylinder, a rotor in said cylinder and eccentric thereto, radially blades carried by said rotor, hangers carried by said blades and extending outside the circumference of the rotor, a circular cam groove surrounding said cylinder, a ring in said groove, separated grooves in said ring opposite each blade, and means connected to said hangers and shiftable in said grooves for causing the blades to follow the curvature of the cylinder wall.

10. A rotary engine comprising in combination a cylinder, a rotor in said cylinder and eccentric thereto, radially movable blades carried by said rotor, hangers carried by said blades and extending outside the circumference of the rotor, a circular cam groove surrounding said cylinder, a ring in said groo\fe, separated grooves in said ring opposite each blade, means connected to said hangers and shiftable in said grooves fo-r causing the blades to follow the curvature of the cylinder, and means for preventing the leakage of steam around said ring.

11. A rotary engine comprising in combination a cylinder, a ro-tor in said cylinder' and eccentric thereto, radially movable blades carried by said rotor, hangers carried by said blades and extending outside the oircumference of the rotor, a circular cam groove surrounding said cylinder, a ring in said groove, separated grooves in said ring opposite each blade, means connected to said movable K hangers and shiftable in said grooves for causing the blades to follow the curvature of the cylinder, means for preventing the leakage of steam around the back side of said ring, and means connected with the rotor and engaging the front side of the ring for sealing the end of the cylinder.

12. A rotary engine comprising, in combination, a casing having a cylinder bore, a ro-tor eccentrieally mounted therein and contacting the surface of said bore for an appreciable distance, a steam supply passageway extending to said bore substantially at the point where the rotor surface and the cylinder surface diverge, an exhaust passageway leading from the bore at a point opposite the said supply passageway, an exhaust port located between vsaid supply passageway and said exhaust passageway, and a condenser connected to said exhaust passageway.

13. A rotary engine comprising, in combination, a casing having a cylinder bore, a rotor eccentrically mounted therein and contacting the surface of said bore for an appreciable distance, passageways leading to each side of the bore and piercing the wall thereof substantially at the points where the surface of the rotor diverges from the bore, an exhaust port located between said passageways, means for admitting steam through either of said passageways, and means for attaching the other of said passageways to a condenser.

14. A rotary engine comprising, in combination, a casing having a cylinder bore, a rotor in said bore, a passageway extending to each side of said bore, a valve arranged to control the flow of fluid to either of said passageways, a cut off valve for each passageway and adapted to be operated by the rotor, the casing being provided with an exhaust port located between said passageways, a by-pass associated with said first-mentioned valve and adapted to convert the passageway which is not at the time operating as an inlet into an auxiliary out-- let, and a condenser attached to said byass.

In testimony whereof, I hereunto aiiix my signature in the presence of two witnesses.

FRANKLIN P. HUMMEL.

Witnesses:

HAROLD E. SMITH, BRENNAN B. VVEs'r.

Copies of this patent may be obtained for ve cents each, by addressing the Commissioner of Patents. Washington, D. CJ? 

